Paper product and method of producing the same



Patented Feb. 10, 1931 PATENT OFFICE WILLIAM CLARENCE. LODGE, OF FULTON,NEW YORK, ASSIGNOR T0 OSWEGO FALLS CORPORATION, OF FULTON, NEW YORK, ACORPORATION OF NEW YORK PAPER PRODUCT AND METHOD OF PRODUCING THE SAMENo Drawing.

view, I have discovered that paper products where sizing is added duringthe paper making process, attain economy in production combined withapproximately maximum (at) strengtl'i, and (6) water resistancequalities, when the product contains not more than approximately onepercent wax or its equivalent, and not more than approximately threepercent rosin or its equivalent; and that the preferred method ofproducing such paper product is to add to the pulp in the beater duringthe paper making process, as a sizing, (1) an emulsion or suspension ofrosin or equivalent ingredient equal by weight to approximately threepercent of the pulp and then (2) an emulsion or suspension of paraffinor equivanent water resisting agent or ingredient equal by weight toapproximately one percent of the pulp, and thereafter add to the pulp inthe beater a proportion of suitable fixing or precipitating agent, suchas alum or its equivalent, equal by weight to approximately threepercent of the pulp.

By the term paper products, I include paper or paper board in the sheetor roll, and also paper articles, such as paper containers of variousforms, and paper closures,

such as paper closure disks and paper hood caps, for bottles and othercontainers.

While it is highly 'desirable to provide paper containers and paperclosures, the paper or paper board of which is approximately water proofor of good Water resistant qualities, yet it is exceedinglydisadvantageous to provide paper products of substantially weak papermaterial, wherein the strength of the paper is substantially weakened asthe water resistant quality of the paper is increased, and it is alsoobjectionable to substantially increase paper production costs by reasonof the attainment of substantial water resistant qualities in the paperproduct.

Applicationfiled January 28, 1927. Serial No. 164,382.

It is highly desirable that paper hood caps (paper caps of skirted formdesigned to cover and protect the heads of containers, 'mrticul'arlymilk bottles) be of more or less high tensile strength, and possesssubstantial water resistant qualities, and where such hood caps carry abinder rendering the caps moldable when heated and quick setting torigid securing form, it is particularly desirable that the caps possessthe qualities of strength as well as resistance against the entrance ofmoisture and consequent swelling of the paper material with a tendencyto expand and unduly loosen the binder carrying skirt molded on thebottle neck.

In making my tests under this invention, I have followed sizing methodsin the production of paper or paper board, particularly that gradelofpaper board commonly known as manilla sulphite or oyster pail, and hoodcaps for bottles, made from such board.

It is known to those skilled in the art, that waxes and fats generally,and parafiin specifically, materially improve the water resistance ofpaper and paper products when incorporated intothe sheet of paper eitherby the process commonly known as engine sizing in which process asolution, emulsion or finely dispersed suspension of wax or waxes aloneor in combination with rosin and/or other ingredients, is added to thepaper pulp in the heaters; or when the wax is applied to a.

surface of the finished sheet of paper by immersion in a bath of moltenwax, or by any other convenient method.

However, I find that the addition of any of these sizing materialsand/or compounds to the paper pulp in the beater, has a marked weakeningeffect on the tensile strength of the finished sheet or paper product.

I have tested paper products the pulp for which was subjected to variousengine sizing treatments during the paper making process, and in thefollowing tables I have tabulated various results attained and comparedthe same with the results attained with paper products of andproducedaccording to, 'my invention.

In the following tables, and explanations, the percentage or proportionof size added to ion the pulp, indicates approximately the amount ofsizing material in the finished sheet or paper product independent ofthe concentration of the emulsion or suspension of the size asintroduced.

Parafiin in the following tables means an aqueous emulsion or suspensioncontaining substantially pure parafiin wax as the only sizing agent inthe preparation.

50-50 paraffin. and rosin, hereinafter means that approximately equalweights of rosin and parafiin wax were fused and then emulsified orfinely dispersed in water.

Rosin hereinafter means the ordinary rosin size of commerce, that is asolution of sodium resinate containing more or less free or unsaponifiedrosin, (in this instance 30% of the total rosin present).

As to the tensile strength of variously sized finished paper, my testsshow as follows, an unsized sheet of paper board being used as astandard:

Decrease (1) Size added Strength n Strength 90% 10% 75% 25% 40% 50% 50%1% paraffin and 2% lOS1I1 85% 16% 1% paraffin and 3% rosin 80% 20% 2%parafiln and 2 rosin 75% 25% I find that paraifin wax has a weakeningeffect on the strength of the sheet, that this effect increases with theamount added, although not in exact proportion to it. I also find byblending wax and rosintogether and then emulsifying the resultantmixture that a compound is formed which exerts proportionately a greatereffect on the strength of 'the finished sheet than paraflin alone.

(2) I find the sizing efiiciency of the various mixtures is not 1nplroportion to their amount or composition. he effect of these variousmixtures on the water resistance of the paper in whiohthey are used istabulated below and the results are expressed as percent of waterabsorbed by sheets of uniform thickness when submerged in distilledwater at a temperature plus or minus Fahrenheit for exactly twentyminutes.

Percent Size added moisture absorbed 1% paraffin"... 35 (1% paraifln 242% 5050 paramn and rosin 38 5% 50-50flparaflln and rosin 26 1% para tiand 2% rosln 28 1% parafiln and 17 r0sln 32 1% paraffin and 3 a realm.24 2% pamflin and 2% rosin 28 3% n in I find that while rosin of itselfis very inferior to wax alone, that the combination of the rosin withthe wax materially improves the sizing properties of the rosin, so muchso that approximately 1% of wax in the finished sheet is suliicient forall practical purposes and may be taken as the optimum amount.

I find that greater efliciency is obtained by the use of separatelyprepared emulsions or suspensions of rosin and wax. It is also ob servedthat this method produces a stronger finished product than any of theothers enumerated. i

(3) I find that when wax and rosin are used in this way, the retentionof the rosin is materially improved, for example: To 1000 pounds of pulpin the beater is added 30 pounds of rosin as emulsified size followedafter an interval of ten minutes by 30 pounds of alum, the stuff passedthrough a Jordan englue and formed into board on a cylinder machine.

The finished board contained 2% of resinous material of which 1.2% waspresent in the original pulp, leaving .8% which has been absorbed in thesize, showing a retention of L976 01 These results were obtained incommercial production. The pulp was less than one hour in the heater,and the board made on a six cylinder machine.

Any substance that will form soluble soap with an alkali, for papersizing purposes, such as stearic acid, stearme, and many vegetable andanimal fats, could be used as a substitute for rosin, for the purposesof my invention, in paper sizing, and hence the term sizing soapemployed herein to include rosin and its substitutes for sizing purposeswithin my invention. However, rosin is at this time preferable becauseit can be readily obtained in the desired quantities at a reasonableprice.

Various substances or compounds can be substituted for paraflin toperform the functions of paraflin within my invention. Any substancethat will perform the functions of paraflin under my invention and thatis susceptible of emulsification, or that will exist in a fine state ofsubdivision, in an aqueous menstruum, can be substituted for paraffin,for instance, ceresin, Montan, carnauba, and Japan wax, beeswax, asphaltemulsions, and emulsions of oils and/or fats, the latter as distinmoaeeaaflim As at present advised by experience and market conditions, Iprefer to employ parafin, or mixtures of parafin and carnauba or MontanWaxeswith rosin.

Where the paper product of my invention will be exposed to heat, sayabove the melting point of parafin, carnauba, or Montan wax or asphaltwould be preferable to paraflin, but on the other hand, the color ofsome of these paraflin substitutes might be objectionable in paperproducts, for some purposes.

What I claim is 1. In the production of a water resistant paper product,those steps which consist in adding to the pulp in the paper makingprocess, approximately 2% to 3% sizing soap such as rosin, andapproximately 1% water resistant ingredient as a sizing, and fixing orprecipitating said sizing in the pulp.

2., In the production of a water resistant paper product, those stepswhich consist in adding to the pulp, sizing in the proportion of threeparts rosin or rosin substitute and approximately one partwax or waxsubstitute, and thereafter fixing or precipitating the same in the pulp,for the final production of paper product containing approximately 1% Iwax and not more than 3% rosin.

In testimony whereof I have hereunto set my hand at Fulton, New York,this 27th day of Jan., 1927.

WM. 0. LOIJGE.

